Flap control and drive systems for aircraft are known in the art. On certain aircraft, for example, the flaps can be controlled by activating a lever or switch which energizes a drive motor to drive the flaps to the selected position. In such systems, the pilot can visually check the condition of the flaps and if the selected position is intermediate between a full-up or a full-down flap position, the pilot can deactivate the lever or switch at an proper intermediate position.
Flap control circuitry permits the pilot to select the position of the flaps by moving the lever to a point corresponding to the desired position of the flaps. The flap control circuitry will energize a motor, which can be mechanically connected through flexible drive couplings, to drive the flaps to the desired position and then cause the motor to be de-energized. The pilot can rely on the control circuitry to drive the flaps to the proper position, and once the pilot has selected the proper flap position, he can devote his attention to flying the aircraft.
However, flaps controlled in this manner raise and lower at the same speed regardless of conditions. During a missed approach or a go-around, pilots apply full engine power, usually with the flaps in the full down position. Correct procedure is to manually raise the flaps in steps so that the lift characteristics of the wing do not change too rapidly. However, this is additional workload for the pilot during a busy and critical time. Accordingly, there is a need for flap control methods and apparatuses that accept high level flap control input from a pilot and determine aircraft operating conditions to apply proper flap control.
Other patents of interest relative to this disclosure include the following, each of which is incorporated herein by reference: U.S. Pat. No. 6,824,099 “Brake systems for aircraft wing flaps and other control surfaces”; U.S. Pat. No. 5,082,208 “System and method for controlling an aircraft flight control member”; U.S. Pat. No. 4,191,347 “Flap control circuitry”.